Separation of vapors and viscous liquids



Feb. 16, 1954 F. H. YuRAsKo ETAL SEPARATION OF VAPORS AND VISCOUSLIQUIDS 2 SheetsSheet l Filed Feb. 18, 1949 Feb 16, 1954 F. H. YURAsKoET AL l 2,669,538

SEPARATION OF VAPORS AND VISCOUS LIQUIDS Filed Feb. 18, 1949 2Sheets-Sheet 2 2 Cltdborl'ne Patented Feb. 16, 1954 1. 2&669538...SEPARATIUNL F ,VAPORS ANDV VISGOUS LIQUIDS Frank Hg:YuraskmiRoseliaand' Howard' lC.v North,

-Vi/estfield, i N J.; assignors tovSsamiardl Oilz DevelopmentCompany, acorporation ofDelaware Application February 18, 1949,"Serial No.' 77,172

z 6, Claims.

The present invention is concernedwith an improved "refining operationand'ismore'specii'lcally concerned with ya method for-securing thegradual dissipation'cf the'energyof flowing streams. 'Theinventionis-especially directed toward the handling 0i'vilowing--strearns whereby the energy ofthe ilowing streamisdissipatedand various phases segregated. `Invaccordance With preferred adaptations-oi the presentl invention viscous liquid streams containing entrainedvaporous constituents arehandled ina manner to eiiciently dissipateftheViiowing energy and to segregate'or separate the vaporous constituentsfrom the viscous-liquid. These-improvements are secured yby shredding'the Tlo'wing stream, by passing lthe same 'into' arnass of fwovenorclosely adhered material.

' ln the'manufactureofvarious chemicals, particularly inthe reninglefffp'etreleuinzfoils, 'itv is necessary to flow streams lfrom onepointito another vand to Vdissipate the energy of the 'iiowing stream ata predeterminedpoint. It is'also necessary in various phases roi rening:operations` to segregate various phases one from-.the otherznas forexample tosegregate la`f-'vapo1ous material from a liquid material. Thissegregation" ofxvapor constituents `from liquid materials.fbecomesz'progressively more -diilicult Vas theviscosity of'fithe liquidincreases since a greater quantity .ofvaporous' constituents `isentrained'` or trappedztherein. One example of Where. this problem .fis.fencountered is in 'the'manufacture,of.;high quality asphalts' frompetroleum oils.

' Inthe manufacture of high. r`quality.f asphalts from petroleum oils,.areducedcrude;containing asphalts is usually subjected-to .afsolventdeasphalting process. One solvent; conventionally `utilized vfor vtheseparation `ofatheoily :constituents from the asphaltic'constituentscomprise propane. However, in an operation of .this character. thevasphalt fraction contains.v `associated therewith a 'relatively` ,largequantity. of .the .solvent, suchaspropane. Thesepara'tion. of thepropane is usuallyaccomplishedby heating the asphaltic stream Lto .atemperature .above the vaporization point of the, propane. Thev heatedliquid asphalt stream containing vaporous solvent is .introduced into aseparation zone which usually comprises a 'iiash separation zone.However, due tothe viscousnature of the liquid,` phase, -itis relativelydifficult to secure a complete and satisfactory separation of thevaporous constituents. One. .expedient Which `has'been utilized in anVattempt to minimize 'this problem is to lemploy relatively largeseparation zones and also to'utilizein (Cl. ISG-1.14146) conjunctiontherewith vabalileplate or similar types-structures. 'The incomingstream is impinged-against the -balile'plate-or caused .tocirculatearound the. periphery of the ash zone. While these methodsserve to secure the desired separation lit-is relatively expensive dueto the size of the equipment'lrequired `for a particular throughput.Furthermore; when relatively heavy viscous liquids are involved, as forexample asphaltic constituentsaa large-degree of foaming and entrainmentoccurs. Thus, it is necessary to employ Ventrainment gseparators,knockout meansand similar equipment.

' It hasfnow been-discovered that'these problems can to a largeextent-be eliminated providing the flowing stream is Aliaiidledvinamanner to progressively Vdissipate its flowing energy. This ispreferably:accomplished4 byV passing the stream into a Woven mass;v suchasa Woven mass of relatively'fine Wire=which contains a relatively largeper cent of free space.

If this be Ldone,.:the iioWing stream is fiinely shredded `intoamultiplicity of streams and the energy of the entire mass'dissipatedprogressively. The present invention is `particularly adapted for themanufactureof .high-quality asphalts. .The invention may be readilyunderstood by reference to theidrawings 'illustrating embodiments of`the same. 'Figure'v 1 illustrates one embodiment of the invention Tasitis applied to the manufacture of highzqualitypetroleum asphalta'whileFigure 2 illustrates :in'somedetail .the'characterof thelamentousmaterial.

Referring specically to Figure 1,;a feed oil which for the purposev of'illustration is assumed tobe affreduced. crude from a asphaltic crudeis introduced into: solvent deasphalting tower Hl by meansc'zfY feedlinel. VA solvent which for the purpose ofillustration is taken tocomprise liqui- .ed propanefis .introduced into zone iii by means ofline2. IIhe` respective phases iiovv countercurrentlyzunder conditions :tosecure intimate mixing of the 'respectivephases ,Temperatureand-pressure conditionsras'vvellas feed rates in zone i9 are maintainedAto.` secure the Y desired separation, andzwillfdependrto. some extentupon the character of the. asphaltic. feed oil` and the particu-larsolventV on solventmixturebeing utilized. Ii propane' be employed, as 4asolvent, a desirable feedfis in the'range .fromabout Gato 10 volumes `of=pro pane per yolumexof oilizfeed. The-temperature maintained in thebottom ofy .the propane tower is in `the Vrange'from about 100' yto 120F., While the r-top-temperature -is inthe range Ifrom about to'-1'60-F.1 It is tobe understood thatsuit 3 able contacting and distributingmeans may be employed within the tower itself.

The oil-solvent stream is removed from the top of zone l by means ofline 3, further heated in heating zone 4 to a temperature above thevaporization temperature of the propane at the existing pressure andintroduced into a flash separation Zone 20. Vaporized propane is removedoverhead from zone by means of line 5 while the oil stream stillcontaining a relatively small amount of vaporized propane is removedfrom zone 20 by means of line 6. In accordance with the presentinvention this stream is introduced into zone by impinging the flowingstream onto and into a mass of fibrous material 40 which preferably compprises a mass of line woven wire. This mass of woven wire is maintainedat the top of distillation zone 30 and is disposed approximately fromabout 6 to 18" away from the end of line B. The incoming streamcontaining vaporous and liquid constituents is shredded into amultiplicity of streams of minute diameter under conditions that thevaporous constituents are effectively and efficiently separated from theliquid constituents in the absence of any foaming whatsoever. Oilconstituents completely free of propane are with drawn from the bottomof zone 30 by means of line l', and handled or further refined in anymanner desired. The freed vaporous propane is withdrawn from the top ofZone 30 by means of line B, and preferably passed through a compressorzone 50. The compressed propane is removed from zone 50 by means of lineSi, passed through a condensing zone S0 and preferably recycled to thesystem by means of line I4.

The asphalt-solvent stream is removed from depropanizing tower i0 bymeans of line H, passed through heating unit l2 which is mainn tained ata temperature above the vaporization point of the solvent. This streamis introduced into zone 50 in a manner to impinge the stream into aweb-like mass of material, preferably into a mass of wire 'l0 maintainedat the top of tower 60. The asphalt stream containing entrained vaporouspropane is shredded into a multiplicity of streams of very smalldiameters. Thus, the energy of the entire flowing stream is graduallydissipated resulting in the release of vaporous solvent. The freedpropane is withdrawn overhead from zone i by means of line I3 and ispreferably combined with the propane removed overhead from zone 20. Thiscombined stream is combined with the compressed propane stream removedfrom Zone 50 prior to passing the combined streams to condenser B0.

A bottoms stream of asphalt containing a relatively small amount ofpropane is withdrawn from zone 60 by means of line i5 and introducedinto Zone 90. Here the asphalt stream is directed into a mass of wovenor equivalent material which preferably comprises a mass of Wire. Theenergy of the stream is gradually dissipated, the propane released andis removed overhead by means of line I6. This stream is preferablycombined with the overhead propane stream removed from zone 30 by meansof line 8. An asphalt stream completely free of propane is removed fromzone 90 by means of line Il and handled or further refined as desired.Figure 2 illustrates in some detail the character of the filamentousmass 'l0 supported in the vapor space of zone 60 by means of suitablesupports 5I.

The present invention is broadly concerned with an improved process forthe dissipation of energy of a flowing stream. This is accomplished byimpinging the flowing stream on a mass of material such as fine wire orother suitable substances. The mass should be finely Woven and shouldhave relatively large proportion of free space, as for example, greaterthan about 50%. It is particularly preferred that the extent of free airspace in the mass be in excess of about and preferably be in the rangeof about -97%. The diameter of the material, as for example wire, shouldbe in the range from about .005" to .020" preferably in the range from.009 to .011". The mass, as pointed out heretofore, may be of anysuitable material, but it is preferred that it be of a metal as forexample, fine wire having a composition adapted to specically resist thecorrosion of any particular corrosive stream. The mass is preferably ofa spongy or of a resilient nature.

The mass employed in the present invention need not be woven, but maycomprise a mat of very porous material. The material may be crinkledwire. Plastic material likewise may be used and substances such assilica fiber. If the stream being treated is at a relatively lowtemperature, the mass may comprise an ordinary carbon steel. If thestream, the energy of which is being dissipated, contains corrosivesubstances such as hydrogen sulphide acidic constituents, as forexample, aliphatic and naphthenic acids, it is preferred that the masscomprise an alloy steel. If the stream being handled contains corrosivesubstances but is at a relatively low temperature, the mass may comprisea copper-nickel steel, as for example, Monel metal. On the other hand ifthe stream being handled is at a relatively high temperature, but isnon-corrosive, it has been found that a steel containing from about 11%to 13% chromium is satisfactory. However, if the stream being handled isat a high temperature and also contains corrosive materials, it has beenfound that a chromium-nickel steel, as for example KAZS is satisfactory.A steel of this character contains about 18% chromium and 8% nickel. Ifthe stream is extremely corrosive a very desirable material to employ asthe mass comprises Tantalum or silica fiber.

The amount of mass of wire or equivalent material utilized may varyappreciably depending upon the velocity of the particular stream it isbeing used in conjunction with, as well as, upon the diameter of thestream and also upon the actual chemical and physical characteristics ofthe flowing stream. However, in general when the diameter of the flowingstream is in the range from about 2" to 6 and the flowing velocity is inthe range from about 15 to 200 per second, it is preferred that the faceof the mass approximate a rectangle having sides from about 9" to 20"and that the thickness of the mass vary in the range from about 3" to12". In general it is preferred that the mass be approximately 6 to 9"thick and that it be disposed from about 2 to 18l away from the inlet ofthe flowing stream in a manner that the stream will impinge at rightangles on the face of the mass.

In a more specific concept of the present invention the process isdirected toward the eflicient releasing of an entrained vapor phase froma liquid phase. This is accomplished by shredding the liquid phasecontaining the entrained vapor phase into a multiplicity of very finestreams thus releasing the vaporous constituents. By operating in thismanner emulsication and Afoaming diculties due to excessive annalisa1 s,intermixing of thev respective phases are elim-i-V nated orsubstantially reduced.

A direct application 01- the present invention is in the manufacture ofAheavy viscous products.

comprise any suitable solvent, but generally com,-

prises a liquied normally gaseous hydrocarbon, as for example propane.The present invention may be more fully understood by the followingexample illustrating an embodiment of the same:

Example An asphaltic reduced crude was countercurrently contacted in apropane tower wherein about 8 volumes of propane were used per volume ofoil. The temperature at Ithe top of the tower was maintained at about150 F., while the temperature in the bottom of the tower was maintainedat about 110 F. Under these conditions approximately 75% of the oilbased upon feed was removed from the top of the tower. The ratio ofpropane to oil in this stream was approximately 12 to l. This stream washeated to about 400 F. and flashed under conditions to remove overhead alarge amount of the propane. The oil stream at about 350 F. andcontaining about 10% of propane was introduced into the top of adepropanizing tower. In accordance with the present invention thisstream was impinged onto and into a mass of steel wire, the dimensionsof which were about 12" x 12 x 6". The free space of the mass employedwas about 95%. Under these conditions substantially no emulsiiication ofthe oil occurred and a rapid and erhcient separation of the propane wassecured. When this method was not utilized with respect to this streamemulsication dihiculties occurred and it was relatively diflicult tosecure complete removal of the propane from the oil phase.

The stream withdrawn from the bottom of the solvent treating towercomprised about 25% of the oil feed. The ratio of propane to oil in thisstream was approximately 1/1. This stream was heated to a temperature ofabout 450 F. and flashed into an initial separation zone whereinsubstantially all of the propane was removed from the asphalticconstituents. In introducing the stream into this initial separationzone, the stream was impinged upon a mass of steel wire, the dimensionsof which were about 12 X 12" X 6". The mass of steel wire comprisedapproximately 95% of free space.

An asphalt stream was withdrawn from the bottom of the initialseparation zone at a temperature of about 450 F. This stream containedapproximately 5% propane. In accordance with the present invention thisstream was introduced into the top of a depropanizing tower and impingedonto a mass of ine steel wire having dimensions of about 12" X 12" X 6".The amount oi free space in the mass itself was about 95%. Rapid andeiiicient separation of the propane was secured from the asphalticconstituents. The propane was removed overhead while the asphalt streamfree of propane was removed from the bottom of the zone. In operationswherein the mass was not employed for shredding, the incoming streamemulsications problems were encountered. It was also relatively dicultto remove all of the propanefrorn the productos-L phalt stream.

As discussed, the invention. is broadly concerned with a process` forthe gradualdissipation of energy. of a iiowing stream, particularly whenthe owing stream isl introduced into:l a vessel of larger diam-eter. byutilizing a mass of nely woven material` in. order to shred the flowing.streamv into a multi.` plicity of ne streams. The invention isparticularly adapted for the segregation. of' vaporous constituents fromliquid.A constituents, especially. when the liquid constituents;y are ofaviscousnature'. The viscosity of a liquid varies, appreciably dependingupon temperature, the:variation.l

depending upon' the coefficient of the particular liquid. However, ingeneral the present invention is particularly adapted,y for the handlingof liquids which have viscosities in excess. of about 200 seconds`Saybolt Universal at100F. Viscous liquids having Furol, viscosities in`excessof about 30 seconds at 275 F; are also, eiliciently handled by thepresent process.

One direct application of the present invention is in the manufacture ofhigh qualityy asphaltsy in a process wherein a liquified normallygaseous hydrocarbon is employed in the manufacture of the asphalts andwherein the liquified hydro.- carbon is removed from they productstream. by a.

flashing operation. The viscosity. ofthe asphaltv streams in themanufacture of high qualityy asphalts are usually in the rangefromabout30 to about 1200 seconds Furol at 300 F. If higher temperatures beemployed, as. for example in the range from about 425-475" F., the Furolviscosities are in the general range from about 30-50 seconds Furol.

The size of the resilient mass employed, as pointed out heretofore, mayvary appreciably. However, in general it is preferred that thedimensions of the sides of the face of the mass upon which the stream isimpinged be from about 1% to three times the diameter of the owingstream. The thickness or depth of the mass likewise should be from about1/2 to 11A times the diameter of the flowing stream impinged thereon.

Having described the invention it is claimed:

l. Process for the separation of entrapped gaseous constituents from aviscous liquid flowing in a conduit, said viscous liquid beingcharacterized by having a viscosity from about 30- 1200 seconds Furol at300 F. which comprises heating said viscous liquid to a temperatureabove the vaporization temperature of said entrapped gaseousconstituents, passing said heated viscous liquid from said conduitthrough a vapor space at a high velocity into a separation Zone andimpinging said viscous liquid onto and into a resilient mass of alamentous material maintained in said separation zone, said mass beingcharacterized by having a thickness in the range from about 3 inches tol2 inches and being further characterized by having at least 50% freespace, whereby separation of said gaseous constituents and the viscousliquid is secured, removing the gaseous constituents from the top ofsaid separation zone and said viscous liquid from the bottom of saidseparation zone.

2. Process as defined by claim 1 wherein said ilowing stream is impingedupon a woven resilient mass of filamentous material, which mass ischaracterized by having at least of free space.

3. Improved process for the separation of asphaltic constituents fromhydrocarbons which comprises adding a liqueed normally gaseous This: isvaccdmplishedv hydrocarbon to an asphaltic oil, separating an asphaltphase containing a portion of said liqueed normally gaseous hydrocarbon,heating said asphalt phase to a temperature above the vaporizationtemperature of said liquefied normally gaseous hydrocarbon, passing saidheated stream from a conduit through a vapor space at a high velocityinto a separation zone and impinging said stream onto and into aresilient mass of filamentous material maintained in said separationzone, said mass being characterized by having a thickness in the rangefrom about 3 inches to 12 inches and being further characterized byhaving at least 50% free space whereby separation of the vaporoushydrocarbons and the liquid asphalt is secured, removing the vaporoushydrocarbons from the top of said separation zone and liquid asphaltfrom the bottom of said separation zone.

4. Process as deiined by claim 3 wherein said liquefied normally gaseoushydrocarbon comprises propane and wherein said asphalt stream is heatedto a temperature about 400 F.

5. Process as dened by claim 3 wherein the velocity is in the range from15 to 200 linear ft. per second.

6. In an apparatus for disengaging a gaseous fluid from a liquid inwhich the said liquid and gaseous fluid is introduced to an intermediatelevel of a vertically elongated disengagement vessel through a conduitinlet at a sufiiciently high ow rate to enter the said Vessel as a solidiiuid stream, the improvement which comprises a mass of fine filamentoussolids positioned within said vessel directly in line with fluid ow fromthe said 8 inlet, said lamentous solids being characterized by a freespace of more than about and having a filament diameter in the range ofabout 0.005 inch to 0.02 inch, said mass of filamentous solids beingspaced from the said inlet at a distance of about 1 to 3 times thediameter of the said inlet, whereby said fluid stream impinges directlyon said lamentous mass causing said gaseous fluid and liquid todisengage to permit removal of gas from the upper portion of saidvessel, and liquid from the bottom portion of said vessel.

FRANK H. YURASKO.

HOWARD C. NORTH.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 1,240,385 SWeetland Sept. 18, 1917 1,255,018 Jones Jan. 29,1918 1,379,056 Smith May 24, 1921 1,463,990 Wilson Aug. 7, 19232,018,871 Pier et al. Oct. 29, 1935 2,110,845 Whiteley Mar. 8, 19382,420,115 Walker et al May 6, 1947 FOREIGN PATENTS Number Country Date529,990 France Sept. 22, 1921 OTHER REFERENCES Chemical EngineersHandbook, John H. Perry, Editor, third edition, McGraw-Hill Book Co.,Inc., New York, 1950, pages 967-68; 1022-27.

1. PROCESS FOR THE SEPARATION OF ENTRAPPED GASEOUS CONSTITUENTS FROM AVISCOUS LIQUID FLOWING IN A CONDUIT, SAID VISCOUS LIQUID BEINGCHARACTERIZED BY HAVING A VISCOSITY FROM ABOUT 301200 SECONDS FUROL AT300* F. WHICH COMPRISES HEATING SAID VISCOUS LIQUID TO A TEMPERATUREABOVE THE VAPORIZATION TEMPERATURE OF SAID ENTRAPPED GASEOUSCONSTITUENTS, PASSING SAID HEATED VISCOUS LIQUID FROM SAID CONDUITTHROUGH A VAPOR SPACE AT A HIGH VELOCITY INTO A SEPARATION ZONE ANDIMPINGING SAID VISCOUS LIQUID ONTO AND INTO A RESILIENT MASS OF AFILAMENTOUS MATERIAL MAINTAINED IN SAID SEPARATION ZONE, SAID MASS BEINGCHARACTERIZED BY HAVING A THICKNESS IN THE RANGE FROM